“All three were from High Wycombe in Buckinghamshire. They were travelling to a family wedding in the Greater Manchester area when the car they were travelling in crashed on the M6 motorway in Staffordshire, near to junction 15.”

The spokesman added: “Specially trained liaison officers have been appointed to support them at this incredibly difficult time for the family.”

Chief Superintendent Martin Evans, of the Central Motorway Police Group, described the incident as “unimaginably sad and tragic”.

He said: “The thoughts of all officers and emergency services colleagues involved are with the bereaved families at this extremely difficult time.”

Meanwhile, officers have issued a public appeal for more information to try and piece together what might have caused the accident, which is believed to have involved only one vehicle, that carrying the family.

Investigations are in the hands of the CMPG Collision Investigation Unit.

The incident led police to close the motorway in both directions for three hours from junction 14 at Stafford, to junction 15 at Stoke.

At the crash scene, medical staff were supported by two air ambulances and colleagues from the fire and police services.

just after the accident, West Midlands Ambulance Service spokesman John Hawker said: “Crews arrived to find a single vehicle that had crashed and overturned.

“Two children and an adult that were travelling in the vehicle suffered serious injuries.

“Unfortunately, despite the best efforts of ambulance crews, nothing could be done to save the two boys and one woman, and they were confirmed dead at the scene.

“Two other women travelling in the car both received emergency treatment at the scene for their injuries and were transferred by land ambulances to University Hospital North Staffordshire on blue lights for further treatment.”